Rear bumper for an automobile



FIG. 1 is a front perspective view of a rear bumper for an automobile of my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a bottom plan view thereof; and,

FIG. 6 is a right side view thereof, the left side view being a mirror image of FIG. 6.

As used herein right and left refer to the orientation of the design depicted in the figures above, not the right and left sides of the device when it is included as a component of an automobile. 

The ornamental design for a rear bumper for an automobile, as shown and described. 